First, why did you bleed the brakes? Because you repaired/replaced parts? Because it started feeling spongy(mushy)? With abs brakes you do not want to run out of fluid or drain the fluid. To flush without the Ford NGS star tester (bongo bucks) the best way is to bleed the system into a container at each wheel while continually checking/adding new dot 3 fluid. do this until the fluid coming out is clean or you think it has all been replaced. If you did run out of fluid and the abs controller has air in it you will need to take it to a shop that has the NGS or an abs sequencer. Some of the reasons for spongy brakes are: Air in the system, leaks in the master cylinder, softened brake hoses, moisture in the fluid and power rake booster defects.